1. Field of the Invention
This invention relates to cameras having focal length variable optical system, particularly zoom lenses with automatic operating means therefor, and more particularly to improvements of the same.
2. Description of the Prior Art
The camera whose optical system is variable in focal length, particularly under zoom control, may be shot in such a fashion that an exposure is being made in accompaniment with zooming from one side to the other. In the thus-taken photograph, the image looks like flowing radiately from the center of the area of the picture format. To get such an imaging effect, it is essential that the alignment of the camera to the target area be steadily held during the shooting. With the prior known camera, however, because of its having a manual operating mechanism for the zoom lens, the photographer has to co-ordinate the shutter with the zoom lens in such a way that, for example, the shutter button is pushed down by his right hand, while simultaneously the zoom ring is manipulated by his left hand. This often led to a hand shake. Another prerequisite is that the initiation of an exposure operation and the start and speed of zooming movement are brought into good timing. This skill is very difficult to acquire.